The present invention relates to a connecting element for joining two support members absorbing tensile forces, which connecting element comprises at least a first and a second casing body with a through-hole for receiving the respective support members, which casing bodies can be joined together by way of a joining section at a first end of each casing body, the opposing second end of each casing body being provided with locking members for holding the support members fast.
The invention has applications in the construction industry but is not confined to this. Connecting elements, or so-called wire locks, are used for joining support members, such as wire cores in bracing wires, together. Joining can be done during the actual process of assembling a cable consisting of a number of such bracing wires, where tightening of each bracing wire is done separately.
When the wire is tensioned with the required force, the wire can be permanently locked by means of a wedge arrangement against a foundation on a structural part that is to be braced. The connecting element can then be removed from the tensioned wire and fixed to a new wire for drawing.
Cables are used primarily for anchoring various structural parts to one another, such as structural parts in bridges, masts, buildings etc. These cables may be used on the one hand for staying once the structural parts are assembled, and on the other during actual building of the structure. Cables comprising such support members, such as wires, may be used in bridge structures such as suspension bridges, cable-stayed bridges etc.
Known wire locks generally suffer from the disadvantage that they are awkward to handle and take a long time to assemble and dismantle, which results in high costs. They also have a tendency to come unscrewed and/or to nip the wire core, which makes dismantling of the casing body more difficult. Nipping of the various parts in known wire locks furthermore means that they sit so tight fast after drawing of the wire that the devices must be scrapped, which results in high costs and unnecessarily high material consumption.
Known systems suffer therefore from lack of flexibility, primarily when dismantling, since these design constructions often nip the wire. In some embodiments, the designs according to the prior art have wedges, which cause the problem described above. Wedges are commonly encountered in prestressed concrete fittings. The wedges in the design according to the prior art also have the capacity to go askew in the casing part through which the wire runs, which further complicates handling and makes this unnecessarily expensive.
Nor can the wire be rotatably connected to the design construction according to the prior art. This means that unnecessary torque acts on the connecting element, with the risk of the latter coming unscrewed.
The object of the invention is to produce a connecting element, which produces axial locking of the support member, whilst the latter is free to rotate in the connecting element.
Another object of the invention is to produce a connecting element, which can be locked in its working position, that is to say in the position in which drawing of a bracing wire may take place, for example.
The connecting element must also have as few projecting parts as possible so that, for example, a wire cannot catch in these during the actual construction work.
The connecting element must furthermore offer good flexibility, permit controlled assembly and dismantling and provide safe use for construction personnel when, for example, fitting and detaching a draw wire from a bracing wire, such as are commonly used, for example, in the construction of a bridge, structure, etc. The draw wire may be a wire of the same material and dimension as the wire core of the bracing wire that is to be drawn, but may also be of some other material and with another dimension. The draw wire may thus be used in a recurrent operation when drawing a number of bracing wires.
This is achieved by a connecting element of the aforementioned type, in which in a working position the locking member of at least one casing body produces an axial locking of the support member running through the casing body by way of a stop part created on the support member within the area of the second end of the casing body.
Further solutions to the object of the invention and characteristics of the invention are specified in the other claims.
The invention means that the risk of fracture markings on the wire core is reduced, since the connecting element according to the invention permits rotation of the wire.
The invention means that a connecting element has been produced that can be quickly and easily locked in the working position and prevents this coming unscrewed, which is undesirable.
Such a connecting element also reduces the number of parts significantly compared to the prior art, which provides greater operating reliability. Because the wire core or the connecting element is free to rotate, undesirable stresses in the wire or torsional forces acting on the draw wire or the bracing wire are avoided. Nor do any torsional forces occur that might cause the connecting element to come unscrewed.
The object is furthermore to produce a connecting element that can be rapidly fitted to and detached from a bracing wire during the construction of a structure, in order to thereby save construction costs.
This is achieved by a method of fitting support members to a building construction by means of the connecting element of aforementioned type, which method involves passing the draw wire through a cable duct together with the connecting element so that the connecting element ends up in an area of a first foundation, connecting a bracing wire to the connecting element coupled to the draw wire, passing the bracing wire through the cable duct in the opposite direction by means of the draw wire and the assembled connecting element so that the connecting element ends up in an area of a second foundation, fixing the bracing wire to the first or second foundation respectively, and detaching the connecting element from the bracing wire.
Such a method provides a quick and simple way of applying a support member, such as a bracing wire, to a construction, such as a cable-stayed bridge.